Discussions on the constructivist mailing list are proving very fruitful – at least I am writing down thoughts I am mulling around. Here another excerpt:
Is a house real? Its constituent parts (cement, bricks)? Does one have to go further down? Is only a completely reductionist account real?
No – all constructions. I propose a minimalist ontology:
There exists a world.
Do not take this sentence literally -> it is an approximation to the unspeakable. To quote from the first verse of the Dao De Jing of Lao Dsi:
“The Dao that can be named is not the eternal Dao.”
It is an assertion of the reality which we are experiencing. All else is a construction, which is true (and therefor knowledge) if it captures aspects of reality relevant for the concrete observer (very related to Nietzsche’s Perpectivism; identical to it? I don’t know yet – have to read and think more 
).
